Fiber optic module connector cleaning slide

ABSTRACT

A slidable planer window cover that secures an optical connector in a fiber optic module. The cover is notched to form a rectangular opening, the notch defining two adjoining sides of the rectangle, a base and a base cover forming the other two sides. The window cover is slotted to allow a screw to pass through from the outside—with respect to the module—and be secured to the base on the other side. When the screw is tightened against the window cover, sliding motion is restrained. Flexible clips on opposing sides of the connector retain the connector within the rectangular opening when the window cover is secured by the screw in a closed position. When the screw is loosened, a removal tab on the window cover facilitates sliding the cover to the extent allowed by the screw, to enlarge the opening thereby facilitating removal of the connector.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. 119(e) to McLain, etal., U.S. provisional patent application No. 60/343,295 entitled “ModuleFiber Optic Connector Cleaning Slide”, which was filed Dec. 22, 2001,and is incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates, generally, to communication networks and, moreparticularly, to providing maintenance access to modules at networknodes.

BACKGROUND

As broadband networks continue to move from the experimental realm tothe order of the day for network and service providers, thecompetition-driven need for providers to reduce costs of implementationincreases proportionally. Community Antenna Television (“CATV”) hastraditionally relied on metallic coaxial (“coax”) cabling to delivervideo signals. Increasingly, optical fiber networks are used totransport analog and digital information signals from a provider tosubscribers. Connection is typically made to the network with a dropcable between the subscriber's premise equipment and a node mounted nearthe subscriber, the mounting method typically being strand mounted orpedestal mounted. In fiber to the home systems, the drop cable as wellas the network side fiber cable typically connect to modules within themodule. Even in fiber to the curb systems where coaxial cable is used toconnect to the subscriber's premises, the network side module in thenode may connect to the network fiber optic cable.

At the node, fiber optic cable or cables are connected to optic fiberconnectors within the node. Damage to the fiber optic cable connectorsmay result from lax cleaning and maintenance practices, or when newadditional modules are added or replaced within a node housing whensubscribers are added or defective modules are replaced. In a fibercommunication system, cleanliness in critically important in providingthe best system performance possible. Dust and other contamination atthe interface of the fiber cores (fiber core and core of module opticalinterface) causes performance degradation.

Accordingly, the connector interface must be as free as possible ofcontamination. As dirty fiber connectors are a common source of lightloss at a node's optical module interface, cleaning of node connectorsis an important maintenance activity to ensure that the changing andmaintenance of a module or modules within a node does not lead tocontaminate entry into the node and to migration to the opticalconnector. In cleaning module connectors, some typical items usedinclude lint-free alcohol pads, alcohol saturated swabs, compressed airdirected toward the connector and inspection a magnifying glass toinspect the connector ferrules.

To clean a connector that is inside a module, it is possible to removethe module from the node. However, this is undesirable because of thetime cost incurred to disconnect optical and electrical cablingconnected to the module and unscrewing the module from the node housing.Thus, it is desirable to have the module remain installed in the nodehousing. Some attempted solutions have included designing an opticalmodule with a removable cover so that the module can remain installed inthe housing while cleaning maintenance can be performed with the coverremoved.

While the removable cover may provide access to the connectors, thenumber of fasteners that secure a cover to the rest of the module behigh enough such that the time is consumed by maintenance personnel inremoving the cover plate and reinstalling the cover. Not only is thetime required high, based on the number of fasteners, but the screws, orsimilar fasteners, are often small, requiring time-consuming patience bymaintenance personnel while removing, and trying to start each fastenerinto its corresponding hole following maintenance, while the module isstill installed hanging from a aerial strand. Thus, there is a need fora module design that allows access to an optical connector enclosedtherein for cleaning thereof without the need for either removing themodule or removing an entire module side cover.

In addition, when a module is removed or replaced for maintenancepurposes, an omega-shaped lifting ring is often inserted into holes inthe module top corresponding to each leg of the ring. If the ring isinserted too far into the module, damage, including electricallyshorting internal components, may occur. Thus, there is a need for alifting mechanism that facilitates the lifting of the module from thenode housing without potentially causing damage to internal componentsof the module.

SUMMARY

An objective of the invention is provide a movable window cover tofacilitate removal of an optical connector from an optical fiber module.A rectangular window cover having a rectangular notch in a cornerintended to be proximate the center of the module slides in a channeland is held the channel by an overhang of a cover that covers the sideof the module. Thus, the notch forms two sides of a rectangular opening,the base of the module and the overlap of the side cover forming theother two.

A slot in the window cover allows a screw to pass there through and intocorresponding threads on the other side of the cover formed into thebase. When the screw is tightened against the window cover, the windowcover is secured in place such that the optical connector may be securedto the module by flexible retaining clips affixed to opposing sides ofthe connector. To prevent withdrawal of the connector from the module,one of the retaining clips bears against one side of a shoulder formedinto the base and the other bears against a first side of the windowcover along an edge of the notch that is parallel to the shoulder. Earson the opposing sides of the connector corresponding to the clips limittravel of the connector inward to the module. Such a connector is knownin the art and is described herein for purposes of describing thecooperation of the various parts of the invention described more fullyelsewhere herein. A removal tab at an end of the window cover oppositethe notch may be used by personnel to slide the window cover along aguide channel, and when tightened against the window cover, may be usedto remove, or insert, the module into the node housing in which it isused.

Generally described is an optical fiber module comprising a base forlocating components internal to the module, the base defining a windowand a movable means coupled to the base for covering the window. Themovable means defining an opening for receiving an optical connector.The module may define an open side and have a removable means forcovering the open side.

The window covering means may be slidably coupled to the base and mayfurther comprise a means for fastening the window covering means to thebase in a closed position. The fastening means may include a threadedscrew or a spring loaded retaining clip.

The base may include a stop shoulder at a side of the widow proximatethe center of the module for engaging, in cooperation with the windowcovering means, the connector to prevent its movement into the module.The window covering means may also include a removal tab at an enddistal to the center of the module when the window cover means in aclosed position.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a perspective view of an optical network module withcleaning slide.

FIG. 2 illustrates an elevation view of the module cleaning slide withthe module laying on its side, the optical connector being removed fromthe module.

FIG. 3 illustrates a plan view of the optical cleaning slide with modulelaying on its side where the optical connector is installed and themodule side cover is removed.

DETAILED DESCRIPTION

As a preliminary matter, it readily will be understood by those personsskilled in the art that the present invention is susceptible of broadutility and application. Many methods, embodiments and adaptations ofthe present invention other than those herein described, as well as manyvariations, modifications, and equivalent arrangements, will be apparentfrom or reasonably suggested by the present invention and the followingdescription thereof, without departing from the substance or scope ofthe present invention.

Accordingly, while the present invention has been described herein indetail in relation to preferred embodiments, it is to be understood thatthis disclosure is only illustrative and exemplary of the presentinvention and is made merely for the purposes of providing a full andenabling disclosure of the invention. The following disclosure is notintended nor is to be construed to limit the present invention orotherwise to exclude any such other embodiments, adaptations,variations, modifications and equivalent arrangements, the presentinvention being limited only by the claims appended hereto and theequivalents thereof. Furthermore, while some aspects of the presentinvention are described in detail herein, other than details describedelsewhere herein, no specific metallic, plastic or other material,housing or module chassis shape, or connector style, for example, isrequired to be used in the practicing of the present invention.

Turning now to the figures, FIG. 1 illustrates a fiber optic module 2for interfacing with an optical fiber. Base 4 is preferably cast from astrong and light material, such as aluminum. Base 4 provides structuralrigidity to the module and provides a foundation for internalcomponents, such as for example, amplifiers, optical fiber, electricalcomponents, etc. In one aspect, base 4 is L-shaped having an open side,which may be covered with L-shaped module cover 6. It will beappreciated that module 2 could be otherwise shaped, but the cutout thatcreates the L-shape facilitates access to connector 8 and window cover10 when the module is installed into a node housing.

Connector 8 provides an interface between network fiber external to thenode and components inside module 2, and removal from the module may berequired to facilitate cleaning of the connector. To avoid the need forremoving a plurality of screws retaining cover 6 to base 4 in order toremove connector 8 from base 4, also preferably L-shaped window cover 10may be designed to slide between the base and cover 6. The cutout incover 10 allows penetration of and location of connector 8 into module 2when window cover 10 is in a closed position. Base 4 may include achannel (not shown in the figure for clarity) in which window cover 10may slide. Opposing the channel, module cover 6 includes overhang 12that engages window cover 10 as it slides, thereby urging window cover10 to remain in the channel as it slides therein.

Slot 14 and screw 16 cooperate to limit the range of sliding motion ofwindow cover 10. Screw 16 passes through slot 14 and is coupled tomatching threads formed within base 4. In addition, when screw 16 istightened against window cover 10, sliding motion is prevented due tofriction between the screw and the window cover. Accordingly, when screw16 is loosened enough to allow sliding motion of window cover 10, thewindow cover may still be retained to base 4. This minimizes maintenancedifficulty, because maintenance personnel need not be careful to avoiddropping screw 16 as it may remain attached to base 4, thereby retainingwindow cover 10 thereto. Although cover 10 may be retained with respectto module 2, window cover 10 may slide far enough so that connector 8disengages from being retained by base 4 and window cover 10. The wayconnector 8 is preferably retained will be discussed in reference toFIGS. 2 and 3 infra.

In addition to slidable window cover 10 defining a cutout opening forlocating connector 8, the slidable window cover may also include aremoval tab 18 at an end distal to the center of module 2. Removal tab18 provides a grip surface to facilitate sliding of cover 10. It will beappreciated that when module 2 is mounted into a typical node housing,tab 18 will be facing up when looking into the node. Thus, tab 18 may beused to push window cover 10 towards the center of module 2, or to pullcover 10 away from the center, thereby facilitating removal of connector8. Furthermore, when screw 16 is fastened tightly such that window covermay not slide with respect to module 2, removal tab may also be used topush module into its position in the node housing, or to pull the modulefrom the node housing when removal of the module is desired.

Turning now to FIG. 2, a view of fiber optic module 2 is shown withconnector 8 removed from connector opening 20. Window cover 10 is shownin the closed position, i.e., window cover 10 is in contact with stopshoulder 22 formed into base 4 such that connector 8 may be receivedthrough the opening 20 formed by window cover 10, stop shoulder 22 andoverhang 12 of side module cover 6. In the closed position, screw 16 istypically tight against module cover 10 to prevent sliding of windowcover 10 in channel 24.

When window cover 10 is in the closed position as shown, connector 8 maybe inserted into opening 20 and retained therein by retaining clips 26.It will be appreciated that connector 8 will typically have a retainingclip 26 on two opposing sides of connector 8, but only one is shown forclarity. With reference to the drawing, the retaining clip that is notshown engages base 4 behind stop shoulder 22 and retaining clip 26(shown) engages behind window cover 10 upon insertion of connector 8into opening 20. When connector 8 is inserted into opening 20, theflexible tabs that make up retaining clips 26 move towards the body ofthe connector allowing it to be pushed through opening 20. When ear 28mates with stop shoulder 22, and ear 30 mates with distal edge 32 ofwindow cover 10, connector 8 is prevented from moving further intoopening 20. Distal ends of the tabs on retaining clips 26 spring awayfrom connector 8 when they have been pushed through opening 20 toprevent the connector from being pulled back out through opening 20.Thus, while window cover 10 remains in the closed position connector 8is retained within opening 20.

When screw 16 is loosened, window cover 10 may be slid, preferably usingremoval tab 18, upward (as viewed in the figure) to remove connector 8after it has been installed through opening 20. If window cover 10 isslid a distance enough that the lateral extent of retaining clips 26 isless that the lateral width of opening 20 (which will be greater whenwindow cover 10 has been slid to the right as compared to the closedposition), then connector 8 may be withdrawn from its correspondingmodule through opening 20. It will be appreciated that screw 16 need notbe totally removed, indeed it is preferably left partially screwed intoits corresponding threads. Thus, the likelihood that window cover 10and/or the screw will be dropped is minimized. It will also beappreciated that connector 8 may be removed while side cover 6 remainsinstalled.

Turning now to FIG. 3, a plan view is shown looking at an aspect. Thiswould be the same view if looking at the side of module 2, as shown inFIG. 1, with module cover 6 removed from base 4. Window cover 10 isshown in the closed position with screw 16 tightened against the cover;the hidden lines of slot 14 are shown with dashed lines. Ear 28 ofconnector 8 is shown mated against stop shoulder 22 and ear 30 is shownmated against window cover 10. It is noted that the thickness of base 4in the area around stop shoulder 22 is thicker than window cover 10, thecover being in alignment with the projection of stop shoulder 22 fromthe base. This allows connector 8 to be aligned perpendicularly with theplane formed by shoulder 22 and the outer surface—with respect to theinside of the module—of cover 10. Thus, tabs 26 A and B can bear evenlyagainst the inside of the projection of stop shoulder 22 and the insideof cover 10 respectively to maintain a solid fit of connector 8 withinthe module. Removal tab 18 is shown as having a curved J-hook shape,however other shapes may be implemented by those skilled in the art. Itwill be appreciated that connector 8 may be installed into a module withcover 10 in the closed position and screw 16 tightened there against.

These and many other objects and advantages will be readily apparent toone skilled in the art from the foregoing specification when read inconjunction with the appended drawings. While an L-shaped base andcorresponding side cover, an L-shaped window cover and a J-shapedremoval tab have been shown and described, it will be appreciated thatthese are only exemplary and other shapes and configurations for theseand other components, as compared with the described and illustratedembodiments, may be implemented by those skilled in the art.

Furthermore, other fastening means, instead of a screw may be used toretain the window cover to the base, such as, for example, aspring-loaded tab or retaining clip that projects from the base andthrough the slot in the window cover when it is in the closed position.In addition, the optical connector illustrated in the preferredembodiment is of a type typically used in the relevant art, but otherstyles or shapes, such as, for example, round or rectangular with acontinuous surrounding flange, rather than two ears on opposing sides,may be accommodated by the present invention with slight modificationthat will be readily apparent by those skilled in the art.

It is to be understood that the embodiments herein illustrated areexamples only, and that the scope of the invention is to be definedsolely by the claims when accorded a full range of equivalents.

What is claimed is:
 1. An optical fiber module comprising: a base forlocating components internal to the module, the base defining a window,and a movable means coupled to the base for covering the window, themovable means movable between open and closed positions, and the movablemeans defining an opening for receiving an optical connector when themovable means is in the closed position.
 2. The module of claim 1wherein the base defines an open side, the module further comprising aremovable means for covering the open side.
 3. The module of claim 1wherein the movable means is slidably coupled to the base.
 4. The moduleof claim 1 further comprising a means for fastening the movable means tothe base in the closed position.
 5. The module of claim 4 wherein thefastening means includes a threaded screw.
 6. The module of claim 4wherein the fastening means includes a retaining clip.
 7. The module ofclaim 1 wherein the base includes a stop shoulder at a side of the widowproximate the center of the module for engaging, in cooperation with themovable means, the connector to prevent its movement into the module. 8.The module of claim 1 wherein the movable means includes a removal tabat an end distal to the center of the module.
 9. An optical fiber modulecomprising: a base for locating components internal to the module, thebase defining a window, the base further defining an open side; aremovable means for covering the open side; and a movable means coupledto the base for covering the window, the movable means having open andclosed positions, wherein the base, the removable covering means and themovable means define an opening for receiving an optical connector whenthe movable means is in the closed position.
 10. The module of claim 9wherein the movable means is slidably coupled to the base in a channel,the movable means being maintained in the channel by an overhang of theremovable means.
 11. The module of claim 9 further comprising a meansfor fastening the movable means to the base in a closed position. 12.The module of claim 11 wherein the fastening means includes a threadedscrew.
 13. The module of claim 11 wherein the fastening means includes aretaining clip.
 14. The module of claim 9 wherein the base includes astop shoulder at a side of the widow proximate the center of the modulefor engaging, in cooperation with the movable means, the connector toprevent its movement into the module.
 15. The module of claim 9 whereinthe movable means includes a removal tab at the end distal to the centerof the module.
 16. The module of claim 9 wherein the movable means ismoved into the open position such that the optical connector may beremoved from the module.
 17. The module of claim 16 wherein the moduleremains installed in a node housing when the optical connector isremoved.
 18. The module of claim 1 wherein the movable means is movedinto the open position such that the optical connector may be removedfrom the module.
 19. The module of claim 18 wherein the module remainsinstalled in a node housing when the optical connector is removed. 20.An optical fiber module comprising: a base having an opening configuredfor receiving an optical connector; and a movable window cover forcovering the opening in the base, the movable window cover movable intoopen and closed positions wherein the optical connector may be receivedin the opening of the base when the movable window cover is in theclosed position.